Composite paper



Jan. 19, 1932. G, E, @585 1,841,946

COMPOSITE PAPER Original Filed Sept. 11, 1929 2 Sheets-Sheet l 2 1? 15 515 1? A EL :4

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BY may aem ATTORNEY Jay. 19, 1932. G. E. GIBBS 1,841,946

COMPOSITE PAPER Original Filed Sept. 11, 1929 2 Sheets-Sheet 2 J 15 @fm"BY A TTO/VNE Y Patented Jan. 19, 1932 UNITED STATES PATENT OFFICE GEORGEE. GIBBS, OI ATTLEBORO, MASSACIl' USETTS, ASSIGNOB TO AMERICAN BE-ENFORGED PAPER COMPANY, OF ATTLIEBORO, MASSACHUSETTS, A CORPORATION 01'MASSACHUSETTS Application filed September 11, 1929, Serial No. 991,931.Renewed July 8, 1931.

This invention relates to a multiply paper consisting of two or moresheets of paper ad- 5 sively used as a building and wrapping paper andit is found that under certain weather conditions the outer sheet of themultiply paper shrinks to a pronounced degree when exposed to the rainand sun. This shrinkage of the paper is objectionable because itfrequently causes the marginal edges of the pa-.

per to pull loose from the building structure to which they may benailed or otherwise secured,

The shrinkage of the exposed outer sheet of the multiply paper occursmost frequently in hot climates, and is due largely to the exposed sheetof paper becoming wet by rain and then rapidly dried by the hot sunrays. Under these particular climate conditions the wet outer sheet ofpaper is dried very rapidly and this rapid drying causes the sheet toshrink to a pronounced degree. The shinking pull is imparted to theinner sheet of paper to which the outer sheet is adhesively se cured,with the result that the overall dimen sion of the multiply paper isreduced and this frequently causes the marginal edges of the multiplypaper to be pulled loose from'the supporting structure to which theedges are secured.

W hen the sheets of the multiply paper are secured together by awater-proof adhesive as is the usual case in a multiply building paper,the moisture or rain which wets the outer sheet of paper is prevented bythe water-proof adhesive from reaching the inner sheet of paper, and asa result the inner sheet of aper remains dry and therefore is notSllb]0t8d to a shrinking action like the outer sheet. However, as abovestated, in the constructions employed heretofore, the shrinking actionof the outer sheet of paper im parts a similar contracting pull to theinner sheet of paper, due to the adhesive connection between the sheets.

The present invention therefore seeks to overcome the above mentioneddifliculties caused by the shrinkage of the outer or exposed sheet ofpaper, and an important feature of the invention resides in a compositefabric formed of two or more sheets of paper adhesively securedtogether, and at least one of the sheets of paper bein provided withfolds forming plaits disposed in spaced relation to each other over thesurface of the sheets and adapted to straighten out as the shectshrinks.As a result of this construction the contracting action of the paperwill serve to straighten out the folds or plaits instead of reducing theoverall dimensions of the composite sheet of paper.

The folds or plaits may be formed either longitudinally or transverselyof the exposed sheet of paper or if desired both longitudinally andtransversely of said sheet, and in some cases, for example when eitherface of the composite sheet is likely to be exposed to the weather, thefolds or plaits may be formed in both sheets of paper. In many cases,however, the formation of the plaits in the particular sheet of paperwhich is to be exposed to the weather will be suificient to prevent adecrease in the overall dimensions of the composite sheet due toshrinkage.

It has been proposed heretofore in the construction of multiply paper tosecure the sheets of paper together by a water-proof adhesive such asblack asphaltum. This adhesive is admirably adapted for use inconnection with the present invention, because the conditions whichcause shrinkage of the paper to an obj ectional degree usually occuronly when the weather is hot enough to soften the black asphaltum cementsufliciently to permit creepage between the adhesively connectcd sheetsof paper. I

That is, when plaits are employed in accordance with the presentinvention to prevent the overall dimensions of a sheet of paper frombeing decreased by shrinkage it is important that a creepage action bepermitted between the adhesively connected sheet of paper, and as abovestated when the paper is exposed to weather conditions that will producea pronounced shrinkage of the paper the black asphaltum will be at thetime the shrinkage occurs in a sufficiently soft and plastic conditionto permit the necessary creepage between the difierent sections of theadhesively connected paper, it being understood that the amount ofcreepage that takes place between the different sections ofv the sheetsof paper may be reduced by placing the plaits as close together as founddesirable.

The above and other features of the invention will be hereinafterdescribed in connection with the accompanying drawings illustrating goodpractical embodiments thereof.

In the drawings Fig. 1 is a perspective view of a piece of reenforcedpaper constructed in accordance with the present invention, one of thesheets of paper being turned back to show the reenforcing fibres.

Fig. 2 is a sectional view showing the reenforced paper of Fig. 1 withits marginal edges attached to supporting structure.

Fig. 3 is a view similar to Fig. 2 but shows the exposed sheet of paperafter it has been shrunk.

Fig. 4 on an enlarged scale is a sectional view through a compositefabric having both outer sheets provided with the plaits of the presentinvention.

Fig. 5 is a perspective view of a piece of multiply paper having theplaits extending both longitudinally and transversely and Fig. 6 is aplan view showing the paper of Fig. 5 as secured to a supportingstructure.

While the present invention is applicable to both reenforced andunreenforced multiply paper consisting of two or more sheets of paperadhesively secured together, it has an important field of use inconnection with reenforced paper and has therefore been shown in thedrawings as applicable to reenforced sheets of paper.

In each of the drawings illustrated the multiply'fabric consists of twosheets of paper 10 and 11 reenforced by straightened unspun fibres, 12and 13 extending longitudinally and transversely of the sheets of paperand adhesively secured therebetween by a waterproof adhesive 14 such asblack asphaltum.

In the embodiment of the invention shown in Figs. 1, 2 and 3 the plaits15 are formed in only one of the sheets of paper it being assumed inthis construction that only the plaited sheet 10 of the paper is to beexposed to the rain and sun. The plaits 15 may be produced by foldingthe sheet 10 at spaced intervals to form any desired size plaits whichmay be positioned as close together as found necessary to prevent theshrinkage of the sheet of paper 10 from pulling the marginal edges ofthe composite sheet of paper away from the supporting structure 16 towhich the paper may be secured by tacks 17.

When the outer sheet of paper 10 of Fig. 2 is caused to shrink due toexposure to the weather or by other conditions the contraction whichtakes place in the various portions of this sheet will serve tostraighten out the plaits 10 as shown in Fig. 3 instead of pulling themarginal portions of the composite fabric away from the supports 16 ashas been the case heretofore.

Usually pronounced shrinkage of the exposed sheet will take place onlyat relatively high atmospheric temperatures at which time the blackasphaltum adhesive 1% will be sufliciently soft and pliable to permitone sheet of paper to creep relative to the other thus permitting theplaits 15 to be reduced in size, as shown in Fig. 3 or straightened outwithout tearing the paper.

It will be understood that when the outer sheet becomes wet due toexposure to rain or moisture'it may expand somewhat relative to theinner sheet which is protected from the moisture by the waterproofadhesive, and while this expansion may cause slight puckers to occurtemporarily in the wet sheet it does not injure the paper or pull itloose from the supporting structure.

in some cases it may be desirable to provide the folds or plaits 15 inboth sheets of paper 10 and 11 as shown in Fig. 4 in which case theplaits at the opposite faces of the composite fabric are preferablydisposed in staggered relation to each other as shown.

In other cases it may be desirable to form the plaits bothlongitudinally and transversely of the exposed sheet of paper 10 asshown in Figs. 5 and (S to thereby relieve the marginal edges of thepaper from injurious strains in either direction due to shrinkage. Thefolds or plaits 15 may readily be produced in the sheet 10 or sheets 10and 11 before the sheets are adhesively secured to gether through theuse of any suitable paper folding or plaiting mechanism.

It will be apparent from the foregoing that by employing the plaits 15in accordance with the present invention the difliculties experiencedheretofore due to shrinkage of one of the sheets of a multiply paperfabric is eliminated, and that either or both sheets of paper of thecomposite fabric may shrink, when the construction of the presentinvention is e1nployed, without causing a reduction in the overalldimension of the fabric.

What is claimed is:

1. As an article of manufacture, a multiply building paper comprisingtwo flat sheets of paper of slightly different length adhesively securedtogether, and the outer and longer sheet that is exposed to the weatherbeing provided at spaced intervals with small folds forming plaits thatdecrease the length of the sheet slightly and adapted to straighten outas this sheet shrinks relatively to the other sheet, to thereby preventthe overall dimension of the multiply paper from decreasing under theshrinking action of the outer sheet.

2. As an article of .manufacture, a composite reenforced fabricconsisting of two sheets of paper of slightly different length providedwith reenforcing fibres adhesively secured between them, and the outerand longer sheet that is exposed to the weather being provided at spacedintervals with small folds forming plaits upon its outer face thatdecrease the length of the sheet slightly and adapted to straighten outas this sheet shrinks relatively to the other sheet, to thereby preventthe overall dimension of the composite fabric from decreasing under theshrinking action of the outer sheet.

3. As an article of manufacture, a multiply building paper comprisingtwo flat sheets of paper one of which is slightly larger than the other,and the outer and larger sheet that is exposed to the weather beingprovided at spaced intervals with small folds forming plaits extendinglongitudinally and transversely of the sheet to reduce its size slightly2 and adapted to straighten out as this sheet shrinks relatively to theother sheet to thereby prevent the overall dimension of the multiplypaper from decreasing under the shrinking action of the outer sheet. 54. As an article of manufacture, a composite building paper consistingof two sheets of paper adhesively secured together by a waterproofadhesive that is rendered sufliciently plastic by hot atmosphereconditions to permit a creepingmovement of one sheet relative to theother, and the outer exposed sheet being provided at s aced intervalswith small folds formin plaits that decrease the ,size of the sheet sightly and adapted to straighten out as this sheet shrinks to therebyprevent the overall dimension of the composite paper from decreasinunder the shrinking action of the outer s eet. 5. As an article ofmanufacture, a multia ply building paper consisting of two flat sheetsof paper reenforced by straightened fibres secured between the sheets ofpaper by a waterproof adhesive, and the outer exposed sheet beingprovided at spaced intervals with small folds forming plaits thatdecrease the size of the sheet slightly and which are adapted tostraighten out as this sheet shrinks, to thereby prevent the overalldimension of the composite paper from decreasin under the shrinkingaction of the outer s eet.

In testimony whereof, I have signed my name to this specification.

GEORGE E. GIBBS.

